The sealing principle of ball check valve

The disc of the ball check valve is a sphere covered with rubber or engineering plastic, so its sealing performance is reliable. Ball check valve can be divided into single ball and multi-ball according to the size of its nominal diameter. The sealing principle is: when the pump is turned on, the medium pressure generated by the forward flow of the medium pushes the ball to move, and leaves the sealing surface of the valve seat along the guide column, the check valve is opened, and the medium passes through; when the pump is stopped, the medium flows in the reverse direction. The pressure pushes the ball to roll along the guide column to the sealing surface of the valve seat, closes the check valve, and relies on the pressure of the working medium to generate a certain sealing pressure between the ball disc and the sealing surface of the valve seat to ensure the sealing of the check valve and prevent the medium flow back. Since the contact surface between the disc of the ball check valve and the sealing surface of the valve seat is narrow, it is close to the line seal, so as long as the roundness of the ball is high, it is easy to achieve sealing. Because the sealing surface is narrow, under the same working pressure of the medium, the sealing ratio of the line seal is larger than that of the surface seal, so the sealing is reliable. However, the seal ball of the ball check valve is covered with rubber or engineering plastic, so the working temperature is limited by the material, and the working temperature of the general medium is below 150 degrees Celsius.

Since the ball check valve can use single-ball seal and multi-ball seal, the nominal size can be made very large, and its range is DN200 – DN1200.

More details of check valves, please go to  https://www.mingpinmetals.com/Check-Valve-pl3017724.html